Control apparatus for aircraft

ABSTRACT

When a difference in the SOC among respective batteries is greater than or equal to a first prescribed value, an electric motor control section reduces output power of a cruise electric motor that operates using electric power of a battery with a low SOC and increases output power of a cruise electric motor that operates using electric power of a battery with a high SOC.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2022-054779 filed on Mar. 30, 2022, thecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a control apparatus for an aircraft.

Description Of The Related Art

WO 2021/089948 A1 discloses a hybrid propulsion architecture. The hybridpropulsion architecture includes four electric propulsion systems. Eachelectric propulsion system includes an electric motor that drives apropeller. The hybrid propulsion architecture includes, as a powersource, a first power source that includes a power generator, and asecond power source that includes a battery. The first power source isprovided to the four electric propulsion systems, and supplies electricpower to the four electric propulsion systems. The second power sourceis provided to each electric propulsion system, and supplies electricpower to the corresponding electric propulsion system.

SUMMARY OF THE INVENTION

In the technology disclosed in WO 2021/089948 A1, in a case where thetotal required electric power for each electric propulsion systemexceeds the electric power that can be supplied from the first powersource, electric power is supplied from each second power source to thecorresponding electric propulsion system. In a case where there is adifference among the remaining capacities of batteries of the respectivesecond power sources, there is a problem that there is insufficientelectric power for some of the electric propulsion systems, despitesufficient electric power being able to be supplied to some of the otherelectric propulsion systems.

The present invention has been devised to solve the aforementionedproblem.

An aspect of the present invention is a control apparatus for anaircraft, the aircraft including: at least one power generatorconfigured to generate electric power; at least one first batteryconfigured to store electric power; at least one first electric motorconfigured to operate using electric power supplied from the powergenerator and the first battery; at least one first diode including ananode connected to a side of the power generator, and a cathodeconnected to a side of the first battery; at least one second batteryconfigured to store electric power; at least one second electric motorconfigured to operate using electric power supplied from the powergenerator and the second battery; at least one second diode including ananode connected to the side of the power generator, and a cathodeconnected to a side of the second battery; and a plurality of rotorsconfigured to generate thrust acting on a fuselage. The controlapparatus comprises: an electric motor control section configured tocontrol each of the first electric motor and the second electric motor;and a battery monitoring section configured to monitor a state of chargeof each of the first battery and the second battery. Each of the rotorsis driven by one of the first electric motor or the second electricmotor, or by both the first electric motor and the second electricmotor. In a case where a difference between the state of charge of thefirst battery and the state of charge of the second battery is greaterthan or equal to a first prescribed value, and the state of charge ofthe first battery is lower than the state of charge of the secondbattery, the electric motor control section decreases thrust generateddue to the first electric motor driving the rotor to reduce consumedelectric power of the first electric motor and also increases thrustgenerated due to the second electric motor driving the rotor, comparedto a case where the difference between the state of charge of the firstbattery and the state of charge of the second battery is less than thefirst prescribed value.

According to the present invention, the SOCs of the batteries can bemade approximately equal.

The above and other objects, features, and advantages of the presentinvention will become more apparent from the following description whentaken in conjunction with the accompanying drawings, in which apreferred embodiment of the present invention is shown by way ofillustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an aircraft;

FIG. 2 is a schematic view showing a configuration of a power supplysystem;

FIG. 3 is a control block diagram of a flight controller;

FIG. 4 is a flow chart showing a process of output power control;

FIG. 5 is a schematic view of the power supply system;

FIG. 6 is a schematic view of the power supply system;

FIG. 7 is a graph showing change over time of the SOC of each battery;

FIG. 8 is a flow chart showing a process of output power control;

FIG. 9 is a schematic view of the power supply system;

FIG. 10 is a schematic view of the power supply system;

FIG. 11 is a graph showing change over time of the SOC of each battery;

FIG. 12 is a schematic view of the power supply system;

FIG. 13 is a schematic view of the power supply system; and

FIG. 14 is a graph showing change over time of the SOC of each battery.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment Configuration ofAircraft

FIG. 1 is a schematic view of an aircraft 10. The aircraft 10 of thepresent embodiment is an electric vertical take-off and landing aircraft(eVTOL aircraft). The aircraft 10 includes rotors that are driven byelectric motors. The aircraft 10 generates thrust in a verticaldirection and thrust in a horizontal direction with the rotors. Theaircraft 10 is a hybrid aircraft. The aircraft 10 includes a powergenerator and a battery, as a power source for the electric motor. Theaircraft 10 supplies the electric power generated by the power generatorto the electric motor. If the electric power generated by the powergenerator is insufficient for the required electric power, the electricpower stored in the battery is supplied to the electric motor.

The aircraft 10 includes a fuselage 12. The fuselage 12 is provided witha cockpit, a cabin, and the like. A pilot rides in the cockpit, andsteers the aircraft 10. Passengers or the like ride in the cabin. Theaircraft 10 may be steered in an automated manner.

The aircraft 10 includes a front wing 14 and a rear wing 16. When theaircraft 10 moves forward, the front wing 14 and the rear wing 16 eachgenerate lift.

The aircraft 10 includes eight VTOL rotors 18V. The eight VTOL rotors18V are a rotor 18V1, a rotor 18V2, a rotor 18V3, a rotor 18V4, a rotor18V5, a rotor 18V6, a rotor 18V7, and a rotor 18V8.

The rotor 18V1, the rotor 18V3, the rotor 18V5, and the rotor 18V7 arearranged on the left side of a center line A of the fuselage 12 in theleft-right direction. The rotor 18V2, the rotor 18V4, the rotor 18V6,and the rotor 18V8 are arranged on the right side of the center line A.That is, four VTOL rotors 18V are arranged on the left side of thecenter line A, and four VTOL rotors 18V are arranged on the right sideof the center line A. The VTOL rotors 18V correspond to vertical rotorsof the present invention.

The center of gravity G of the aircraft 10 is positioned on the centerline A of the fuselage 12. When the aircraft 10 is viewed from above,the center of gravity G is positioned between the rotor 18V4 and therotor 18V6 in the front-rear direction of the fuselage 12. Furthermore,the center of gravity G is positioned between the rotor 18V3 and therotor 18V5 in the front-rear direction of the fuselage 12.

When the aircraft 10 is viewed from above, the rotor 18V8 is provided ata position having point symmetry with the rotor 18V1, with respect tothe center of gravity G. The rotor 18V7 is provided at a position havingpoint symmetry with the rotor 18V2, with respect to the center ofgravity G. The rotor 18V6 is provided at a position having pointsymmetry with the rotor 18V3, with respect to the center of gravity G.The rotor 18V5 is provided at a position having point symmetry with therotor 18V4, with respect to the center of gravity G.

One VTOL electric motor 20V is provided for each VTOL rotor 18V.Specifically, an electric motor 20V1_1 is provided for the rotor 18V1.An electric motor 20V2_2 is provided for the rotor 18V2. An electricmotor 20V3_2 is provided for the rotor 18V3. An electric motor 20V4_1 isprovided for the rotor 18V4. An electric motor 20V5_1 is provided forthe rotor 18V5. An electric motor 20V6_2 is provided for the rotor 18V6.An electric motor 20V7_2 is provided for the rotor 18V7. An electricmotor 20V8_1 is provided for the rotor 18V8. Each VTOL rotor 18V isdriven by the corresponding VTOL electric motor 20V.

Each VTOL rotor 18V generates thrust mainly in the upward direction ofthe fuselage 12. The thrust of each VTOL rotor 18V is controlled byadjusting the rotational speed of the rotor and the pitch angle of theblades. If other conditions such as the blade pitch angle are constant,the greater the output power of the VTOL electric motor 20V the greaterthe thrust generated by the VTOL rotor 18V. Each VTOL rotor 18V is usedmainly during vertical takeoff, during a transition from verticaltakeoff to cruising, during a transition from cruising to verticallanding, during vertical landing, during hovering, and the like.Furthermore, each VTOL rotor 18V is used during attitude control.

The propulsion force is applied to the fuselage 12 mainly in the upwarddirection, by controlling the thrust of each VTOL rotor 18V. The rollmoment, pitch moment, and yaw moment are applied to the fuselage 12 bycontrolling the thrust of each VTOL rotor 18V.

The aircraft 10 includes two cruise rotors 22C. The two cruise rotors22C are a rotor 22C1 and a rotor 22C2. The rotor 22C1 and the rotor 22C2are attached to a rear portion of the fuselage 12. The rotor 22C1 isarranged on the left side of the center line A. The rotor 22C2 isarranged on the right side of the center line A. That is, one cruiserotor 22C is arranged on the left side of the center line A, and onecruise rotor 22C is arranged on the right side of the center line A. Thecruise rotors 22C correspond to horizontal rotors of the presentinvention.

Two cruise electric motors 24C are provided for each cruise rotor 22C.Specifically, an electric motor 24C1_1 and an electric motor 24C2_2 areprovided for the rotor 22C1. An electric motor 24C3_1 and an electricmotor 24C4_2 are provided for the rotor 22C2. Each single cruise rotor22C is driven by two cruise electric motors 24C.

Each cruise rotor 22C generates thrust mainly in the forward directionof the fuselage 12. The thrust of each cruise rotor 22C is controlled byadjusting the rotational speed of the rotor and the pitch angle of theblades. If other conditions such as the blade pitch angle are constant,the greater the output power of the cruise electric motor 24C thegreater the thrust generated by the cruise rotor 22C. Each cruise rotor22C is used mainly during a transition from vertical takeoff tocruising, during cruising, during a transition from cruising to verticallanding, and the like. The propulsion force is applied to the fuselage12 mainly in the forward direction, by controlling the thrust of eachcruise rotor 22C.

Configuration of Power Supply System

FIG. 2 is a schematic view of a configuration of a power supply system26.

The aircraft 10 includes, as a drive source of a first drive system 28,the electric motor 20V1_1, the electric motor 20V4_1, the electric motor20V5_1, the electric motor 20V8_1, the electric motor 24C1_1, and theelectric motor 24C3_1. In the following, the electric motor 20V1_1, theelectric motor 20V4_1, the electric motor 20V5_1, and the electric motor20V8_1 may be referred to as the VTOL electric motors 20V of the firstdrive system 28. Furthermore, the electric motor 24C1_1 and the electricmotor 24C3_1 may be referred to as the cruise electric motors 24C of thefirst drive system 28. The VTOL electric motors 20V of the first drivesystem 28 and the cruise electric motors 24C of the first drive system28 correspond to first electric motors of the present invention.

The aircraft 10 includes, as a drive source of a second drive system 30,the electric motor 20V2_2, the electric motor 20V3_2, the electric motor20V6_2, the electric motor 20V7_2, the electric motor 24C2_2, and theelectric motor 24C4_2. In the following, the electric motor 20V2_2, theelectric motor 20V3_2, the electric motor 20V6_2, and the electric motor20V7_2 may be referred to as the VTOL electric motors 20V of the seconddrive system 30. Furthermore, the electric motor 24C2_2 and the electricmotor 24C4_2 may be referred to as the cruise electric motors 24C of thesecond drive system 30. The VTOL electric motors 20V of the second drivesystem 30 and the cruise electric motors 24C of the second drive system30 correspond to second electric motors of the present invention.

The power supply system 26 includes two main power source apparatuses 32and four auxiliary power source apparatuses 34. The power supply system26 supplies electric power to four load modules 36.

The two main power source apparatuses 32 are a first main power sourceapparatus 32 a and a second main power source apparatus 32 b. The fourauxiliary power source apparatuses 34 are a first auxiliary power sourceapparatus 34 a, a second auxiliary power source apparatus 34 b, a thirdauxiliary power source apparatus 34 c, and a fourth auxiliary powersource apparatus 34 d. The four load modules 36 are a first load module36 a, a second load module 36 b, a third load module 36 c, and a fourthload module 36 d.

The power supply system 26 includes two power supply circuits 38. Thetwo power supply circuits 38 are a first power supply circuit 38 a and asecond power supply circuit 38 b. The first power supply circuit 38 aand the second power supply circuit 38 b are provided independently, andare not connected to each other.

Each power supply circuit 38 includes a main power source circuit 40 andan auxiliary power source circuit 42. The main power source circuit 40is provided for each main power source apparatus 32. The auxiliary powersource circuit 42 is provided for each auxiliary power source apparatus34.

Each main power source apparatus 32 includes a gas turbine 44, a powergenerator 46, and a power control unit (referred to below as a PCU) 48.The gas turbine 44 drives the power generator 46. Due to this, the powergenerator 46 generates electric power. The PCU 48 converts AC powergenerated by the power generator 46 into DC power, and outputs this DCpower to the main power source circuit 40. When the gas turbine 44 isstarted, the PCU 48 converts DC power supplied by the main power sourcecircuit 40 into AC power, and outputs this AC power to the powergenerator 46. The power generator 46 operates due to the AC power inputfrom the PCU 48, such that the power generator 46 drives the gas turbine44.

In the following, the power generator 46 in the first main power sourceapparatus 32 a may be referred to as a first power generator 46 a. Thepower generator 46 in the second main power source apparatus 32 b may bereferred to as a second power generator 46 b.

Each auxiliary power source apparatus 34 includes a battery 50. Thebattery 50 is charged by the DC power supplied from the main powersource apparatus 32. In the following, the battery 50 in the firstauxiliary power source apparatus 34 a may be referred to as a firstbattery 50 a. Furthermore, the battery 50 in the second auxiliary powersource apparatus 34 b may be referred to as a second battery 50 b. Thebattery 50 in the third auxiliary power source apparatus 34 c may bereferred to as a third battery 50 c. The battery 50 in the fourthauxiliary power source apparatus 34 d may be referred to as a fourthbattery 50 d. The first battery 50 a and the second battery 50 bcorrespond to first batteries of the present invention. The thirdbattery 50 c and the fourth battery 50 d correspond to second batteriesof the present invention.

The first battery 50 a and the second battery 50 b supply electric powerto the VTOL electric motors 20V of the first drive system 28 and thecruise electric motors 24C of the first drive system 28. That is, thefirst battery 50 a and the second battery 50 b function as power storageapparatuses of the first drive system 28. In the following, the firstbattery 50 a and the second battery 50 b may each be referred to as abattery 50 of the first drive system 28. The third battery 50 c and thefourth battery 50 d supply electric power to the VTOL electric motors20V of the second drive system 30 and the cruise electric motors 24C ofthe second drive system 30. That is, the third battery 50 c and thefourth battery 50 d function as power storage apparatuses of the seconddrive system 30. In the following, the third battery 50 c and the fourthbattery 50 d may each be referred to as a battery 50 of the second drivesystem 30.

Each load module 36 includes two VTOL drive units 52 and one cruisedrive unit 54.

Each VTOL drive unit 52 includes an inverter 56 and the VTOL electricmotor 20V. The inverter 56 converts the DC power supplied by the mainpower source circuit 40 into three-phase AC power, and outputs this ACpower to the VTOL electric motor 20V.

The cruise drive unit 54 includes an inverter 58 and the cruise electricmotor 24C. The inverter 58 converts the DC power supplied by the mainpower source circuit 40 into three-phase AC power, and outputs this ACpower to the cruise electric motor 24C.

The first load module 36 a and the third load module 36 c each include aconverter 60. The converter 60 steps down the voltage of the DC powersupplied from the main power source apparatus 32, and outputs thisvoltage to a device that operates using DC power. The device thatoperates using DC power is a cooling apparatus that cools the PCU 48,the inverter 56, the inverter 58, and the like, for example.

Each main power source circuit 40 includes one common bus 62, onecontactor unit 64, two contactor units 66, one current sensor 68, andtwo current sensors 70.

The common bus 62 connects one main power source apparatus 32 and twoload modules 36. Due to the common bus 62, the two load modules 36 areconnected in parallel to the main power source apparatus 32.

The contactor unit 64 is provided between the main power sourceapparatus 32 and the common bus 62. The contactor unit 64 switchesbetween a conduction state, in which current flows between the mainpower source apparatus 32 and the common bus 62, and an interruptionstate, in which the flow of current between the main power sourceapparatus 32 and the common bus 62 is interrupted. The contactor unit 64includes a contactor 64 a and a contactor 64 b. The contactor 64 a isprovided to the positive wire of the main power source circuit 40. Thecontactor 64 b is provided to the negative wire of the main power sourcecircuit 40. The contactor unit 64 may include just one of the contactor64 a and the contactor 64 b.

Each contactor unit 66 is provided between the corresponding load module36 and the common bus 62. The contactor unit 66 switches between aconduction state, in which current flows between the corresponding loadmodule 36 and the common bus 62, and an interruption state, in which theflow of current between the corresponding load module 36 and the commonbus 62 is interrupted. The contactor unit 66 includes a contactor 66 aand a contactor 66 b. The contactor 66 a is provided to the positivewire of the main power source circuit 40. The contactor 66 b is providedto the negative wire of the main power source circuit 40. The contactorunit 66 may include just one of the contactor 66 a and the contactor 66b. In a case where the contactor unit 64 includes only the contactor 64a, the contactor unit 66 preferably includes only the contactor 66 b. Ina case where the contactor unit 64 includes only the contactor 64 b, thecontactor unit 66 preferably includes only the contactor 66 a.

The current sensor 68 is provided between the contactor unit 64 and thecommon bus 62. The current sensor 68 is provided to the positive wire ofthe main power source circuit 40. Each current sensor 70 is providedbetween the corresponding contactor unit 66 and the common bus 62. Eachcurrent sensor 70 is provided to the positive wire of the main powersource circuit 40.

Each auxiliary power source circuit 42 is connected to both the mainpower source circuit 40 and the load module 36. The auxiliary powersource circuit 42 supplies electric power from the auxiliary powersource apparatus 34 to the load module 36. Furthermore, the auxiliarypower source circuit 42 supplies electric power from the main powersource circuit 40 to the auxiliary power source apparatus 34. Theauxiliary power source circuit 42 includes a contactor unit 72 and acurrent sensor 74.

The contactor unit 72 is provided between the auxiliary power sourceapparatus 34 and the load module 36. The contactor unit 72 switchesbetween a conduction state, in which current flows between the auxiliarypower source apparatus 34 and the load module 36, and an interruptionstate, in which the flow of current between the auxiliary power sourceapparatus 34 and the load module 36 is interrupted. The contactor unit72 includes a contactor 72 a, a contactor 72 b, and a precharge circuit72 c. The contactor 72 a is provided to the positive wire of theauxiliary power source circuit 42. The contactor 72 b is provided to thenegative wire of the auxiliary power source circuit 42. The prechargecircuit 72 c is provided in parallel with the contactor 72 b. Theprecharge circuit 72 c includes a contactor 72 d and a resistor 72 e.The current sensor 74 is provided to the negative wire of the auxiliarypower source circuit 42.

The contactor unit 72 may include just the contactor 72 b and theprecharge circuit 72 c. The precharge circuit 72 c may be provided inparallel with the contactor 72 a. In such a case, the contactor unit 72may include just the contactor 72 a and the precharge circuit 72 c.

A diode 76 is provided between the main power source circuit 40 and eachauxiliary power source circuit 42. The anode of the diode 76 isconnected to the main power source circuit 40, and the cathode of thediode 76 is connected to the auxiliary power source circuit 42. Thesupply of electric power from the main power source circuit 40 to theauxiliary power source circuit 42 is allowed by the diode 76. The supplyof electric power from the auxiliary power source circuit 42 to the mainpower source circuit 40 is blocked by the diode 76. In a case where themain power source circuit 40 has shorted, electricity is prevented fromflowing from the auxiliary power source apparatus 34 to the main powersource circuit 40. As a result, even when the main power source circuit40 has shorted, electric power can be supplied from the auxiliary powersource apparatus 34 to the load module 36.

A transistor 78 is provided in parallel with the diode 76. When thetransistor 78 is ON, the diode 76 is bypassed and electric power issupplied from the auxiliary power source apparatus 34 to the main powersource circuit 40. Due to the electric power supplied from the auxiliarypower source apparatus 34, the power generator 46 can operate toactivate the gas turbine 44.

Among the VTOL rotors 18V arranged on the left side of the center line Aof the fuselage 12 (FIG. 1 ), the VTOL rotors 18V driven by the VTOLelectric motors 20V of the first drive system 28 are the two rotors 18V1and 18V5 (FIG. 2 ). Among the VTOL rotors 18V arranged on the left sideof the center line A of the fuselage 12 (FIG. 1 ), the VTOL rotors 18Vdriven by the VTOL electric motors 20V of the second drive system 30 arethe two rotors 18V3 and 18V7 (FIG. 2 ). That is, among the VTOL rotors18V arranged on the left side of the center line A of the fuselage 12,the number of VTOL rotors 18V driven by the VTOL electric motors 20V ofthe first drive system 28 and the number of VTOL rotors 18V driven bythe VTOL electric motors 20V of the second drive system 30 are the same.

Among the VTOL rotors 18V arranged on the right side of the center lineA of the fuselage 12 (FIG. 1 ), the VTOL rotors 18V driven by the VTOLelectric motors 20V of the first drive system 28 are the two rotors 18V4and 18V8 (FIG. 2 ). Among the VTOL rotors 18V arranged on the right sideof the center line A of the fuselage 12 (FIG. 1 ), the VTOL rotors 18Vdriven by the VTOL electric motors 20V of the second drive system 30 arethe two rotors 18V2 and 18V6 (FIG. 2 ). That is, among the VTOL rotors18V arranged on the right side of the center line A of the fuselage 12,the number of VTOL rotors 18V driven by the VTOL electric motors 20V ofthe first drive system 28 and the number of VTOL rotors 18V driven bythe VTOL electric motors 20V of the second drive system 30 are the same.

The rotor 22C1 arranged on the left side of the center line A of thefuselage 12 is driven by the cruise electric motor 24C of the firstdrive system 28 and also driven by the cruise electric motor 24C of thesecond drive system 30 (FIG. 2 ). That is, among the cruise rotors 22Carranged on the left side of the center line A of the fuselage 12, thenumber of cruise rotors 22C driven by the cruise electric motors 24C ofthe first drive system 28 and the number of cruise rotors 22C driven bythe cruise electric motors 24C of the second drive system 30 are thesame.

The rotor 22C2 arranged on the right side of the center line A of thefuselage 12 is driven by the cruise electric motor 24C of the firstdrive system 28 and also driven by the cruise electric motor 24C of thesecond drive system 30 (FIG. 2 ). That is, among the cruise rotors 22Carranged on the right side of the center line A of the fuselage 12, thenumber of cruise rotors 22C driven by the cruise electric motors 24C ofthe first drive system 28 and the number of cruise rotors 22C driven bythe cruise electric motors 24C of the second drive system 30 are thesame.

Configuration of Flight Controller

The power supply system 26 includes a flight controller 80. The flightcontroller 80 controls the thrust output from each VTOL rotor 18V andeach cruise rotor 22C. FIG. 3 is a control block diagram of the flightcontroller 80.

The flight controller 80 includes a computing section 82 and a storagesection 84. The computing section 82 is a processor such as a CPU(Central Processing Unit) or GPU (Graphics Processing Unit), forexample. The computing section 82 includes an output power command valuecalculating section 86, a battery monitoring section 88, and an electricmotor control section 90. The output power command value calculatingsection 86, the battery monitoring section 88, and the electric motorcontrol section 90 are realized by the computing section 82 executingprograms stored in the storage section 84. At least a portion of theoutput power command value calculating section 86, the batterymonitoring section 88, and the electric motor control section 90 may berealized by an integrated circuit such as an ASIC (Application SpecificIntegrated Circuit) or an FPGA (Field-Programmable Gate Array). At leasta portion of the output power command value calculating section 86, thebattery monitoring section 88, and the electric motor control section 90may be realized by an electronic circuit that includes a discretedevice.

The storage section 84 is formed by a volatile memory (not shown in thedrawings) and a nonvolatile memory (not shown in the drawings) that arecomputer-readable storage media. The volatile memory is a RAM (RandomAccess Memory) or the like, for example. The nonvolatile memory is a ROM(Read Only Memory), a flash memory, or the like, for example. Data andthe like are stored in the volatile memory, for example. Programs,tables, maps, and the like are stored in the nonvolatile memory, forexample. At least a portion of the storage section 84 may be includedthe processor, integrated circuit, or the like described above.

The output power command value calculating section 86 calculates anoutput power command value for each VTOL electric motor 20V, and anoutput power command value for each cruise electric motor 24C. Theoutput power command values are determined according to a manipulationamount of a manipulation input section performed by the pilot. Themanipulation input section is a control stick, a pedal, a lever, or thelike, for example. The manipulation amount of the manipulation inputsection and the output power command value do not need to have aone-to-one relationship. The output power command value may vary withrespect to the manipulation amount of the manipulation input section,according to the manipulation range of the manipulation input section,the manipulation speed of the manipulation input section, the attitudeof the fuselage 12, and the like.

If there is no manipulation input to the manipulation input section bythe pilot, the output power command value may be determinedautomatically to realize hovering, regardless of the manipulation amountof the manipulation input section. Furthermore, in a case where theaircraft 10 is controlled automatically, the output power command valuemay be determined automatically according to a preset flight route,regardless of the manipulation amount of the manipulation input section.

The battery monitoring section 88 monitors the SOC (State Of Charge) ofthe battery 50 of each auxiliary power source apparatus 34.

The electric motor control section 90 controls each VTOL electric motor20V, and sets the output power of each VTOL electric motor 20V to theoutput power command value. The electric motor control section 90controls each cruise electric motor 24C, and sets the output power ofeach cruise electric motor 24C to the output power command value. Theelectric motor control section 90 performs SOC equalization control, asdescribed below.

SOC Equalization Control

The following describes SOC equalization control performed by theelectric motor control section 90.

As an example, in a case where the fuselage 12 experiences a disturbancesuch as a crosswind, the output power of some of the VTOL electricmotors 20V is increased to be greater than the output power of otherVTOL electric motors 20V, in order to fix the attitude of the fuselage12. In this case, a difference occurs between the SOCs of the respectivebatteries 50. The SOC equalization control is control performed toequalize the SOCs of the batteries 50 when a difference occurs betweenthe SOCs of respective batteries 50.

When there is a difference in the SOC between the first battery 50 a andthe second battery 50 b, which are power storage apparatuses of thefirst drive system 28, the SOCs of these two batteries 50 becomeapproximately equal even if the SOC equalization control is notperformed. As shown in FIG. 2 , the first battery 50 a and the secondbattery 50 b are connected in parallel to the first main power sourceapparatus 32 a. The battery 50 with a low SOC has a lower voltage thanthe battery 50 with a high SOC.

Therefore, when a difference occurs between the SOC of the first battery50 a and the SOC of the second battery 50 b, the current flowing fromthe first power generator 46 a to the battery 50 with a low SOC isgreater than the current flowing from the first power generator 46 a tothe battery 50 with a high SOC during charging of the batteries 50. As aresult, the charged electric power amount of the battery 50 with a lowSOC becomes greater than the charged electric power amount of thebattery 50 with a high SOC, and the SOC of the first battery 50 a andSOC of the second battery 50 b become approximately equal.

Furthermore, when a difference occurs between the SOC of the firstbattery 50 a and the SOC of the second battery 50 b, the current flowingfrom the first power generator 46 a to the load module 36 connected tothe battery 50 with a low SOC is greater than the current flowing fromthe first power generator 46 a to the load module 36 connected to thebattery 50 with a high SOC during discharging of the batteries 50. As aresult, the discharged electric power amount of the battery 50 with alow SOC becomes less than the discharged electric power amount of thebattery 50 with a high SOC, and the SOC of the first battery 50 a andSOC of the second battery 50 b become approximately equal.

The third battery 50 c and the fourth battery 50 d, which are powerstorage apparatuses of the second drive system 30, are connected inparallel to the second main power source apparatus 32 b. Therefore, evenwhen a difference occurs between the SOC of the third battery 50 c andthe SOC of the fourth battery 50 d, the SOC of the third battery 50 cand the SOC of the fourth battery 50 d become approximately equal.

On the other hand, the batteries 50 of the first drive system 28 and thebatteries 50 of the second drive system 30 are connected to differentmain power source apparatuses 32. Therefore, when a difference occursbetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30, it is necessaryto perform the SOC equalization control to make the SOC of the batteries50 of the first drive system 28 and the SOC of the batteries 50 of thesecond drive system 30 equal.

With the SOC equalization control, consumed electric power of eachcruise electric motor 24C is adjusted to make the electric powersupplied to the battery 50 with a low SOC greater than the electricpower supplied to the battery 50 with a high SOC. The consumed electricpower of each cruise electric motor 24C is adjusted by controlling theoutput power of each cruise electric motor 24C.

FIG. 4 is a flow chart showing a process of output power control. TheSOC equalization control is performed as a portion of the output powercontrol. The output power control is performed by the electric motorcontrol section 90. This output power control is performed repeatedly atprescribed intervals, while the aircraft 10 is operating.

At step S1, the electric motor control section 90 controls each VTOLelectric motor 20V and each cruise electric motor 24C, based on theoutput power command values. After this, the process moves to step S2.Due to the processing of step S1, the output power of each VTOL electricmotor 20V and each cruise electric motor 24C becomes approximately equalto the output power command value.

At step S2, the electric motor control section 90 determines whether thedifference between the SOC of the batteries 50 of the first drive system28 and the SOC of the batteries 50 of the second drive system 30 isgreater than or equal to a first prescribed value. If the differencebetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 is greater than orequal to the first prescribed value, the process moves to step S3. Ifthe difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30is less than the first prescribed value, the output power control ends.The first prescribed value is set to a value making it possible todetermine that there is a certain degree of difference between the SOCof the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30.

At step S3, the electric motor control section 90 determines whether theSOC of the batteries 50 of the first drive system 28 is lower than theSOC of the batteries 50 of the second drive system 30. If the SOC of thebatteries 50 of the first drive system 28 is lower than the SOC of thebatteries 50 of the second drive system 30, the process moves to stepS4. If the SOC of the batteries 50 of the first drive system 28 ishigher than the SOC of the batteries 50 of the second drive system 30,the process moves to step S7.

At step S4, the electric motor control section 90 determines whether theSOC of the batteries 50 of the first drive system 28 is less than asecond prescribed value. If the SOC of the batteries 50 of the firstdrive system 28 is less than the second prescribed value, the processmoves to step S5. If the SOC of the batteries 50 of the first drivesystem 28 is greater than or equal to the second prescribed value, theoutput power control ends. The SOC of the batteries 50 of the firstdrive system 28 being less than the second prescribed value indicatesthat the SOC of the batteries 50 of the first drive system 28 is lowerthan the second prescribed value. The SOC of the batteries 50 of thefirst drive system 28 being greater than or equal to the secondprescribed value indicates that the SOC of the batteries 50 of the firstdrive system 28 is equal to the second prescribed value or that the SOCof the batteries 50 of the first drive system 28 is higher than thesecond prescribed value. The second prescribed value is set to be arelatively low SOC value. In the subsequent steps S5 and S6, the SOCequalization control is performed.

At step S5, the electric motor control section 90 decreases the outputpower of the cruise electric motors 24C of the first drive system 28, tobe smaller than the output power command value. After this, the processmoves to step S6. Due to the processing of step S5, the consumedelectric power of the cruise electric motors 24C of the first drivesystem 28 is decreased. Furthermore, if other conditions are constant,the thrust generated due to the cruise electric motors 24C of the firstdrive system 28 driving the cruise rotors 22C decreases.

At step S6, the electric motor control section 90 increases the outputpower of the cruise electric motors 24C of the second drive system 30,to be greater than the output power command value. After this, theprocess moves to step S10. Due to the processing of step S6, theconsumed electric power of the cruise electric motors 24C of the seconddrive system 30 is increased. Furthermore, if other conditions areconstant, the thrust generated due to the cruise electric motors 24C ofthe second drive system 30 driving the cruise rotors 22C increases.

At step S6, the thrust generated due to the cruise electric motors 24Cof the second drive system 30 driving the cruise rotors 22C is increasedby an amount corresponding to the amount of the decrease of the thrustgenerated due to the cruise electric motors 24C of the first drivesystem 28 driving the cruise rotors 22C in step S5. As a result, the sumof the thrust generated due to the cruise electric motors 24C of thefirst drive system 28 driving the cruise rotors 22C and the thrustgenerated due to the cruise electric motors 24C of the second drivesystem 30 driving the cruise rotors 22C is kept the same before andafter the SOC equalization control.

At step S7, the electric motor control section 90 determines whether theSOC of the batteries 50 of the second drive system 30 is less than thesecond prescribed value. If the SOC of the batteries 50 of the seconddrive system 30 is less than the second prescribed value, the processmoves to step S8. If the SOC of the batteries 50 of the second drivesystem 30 is greater than or equal to the second prescribed value, theoutput power control ends. The SOC of the batteries 50 of the seconddrive system 30 being less than the second prescribed value indicatesthat the SOC of the batteries 50 of the second drive system 30 is lowerthan the second prescribed value. The SOC of the batteries 50 of thesecond drive system 30 being greater than or equal to the secondprescribed value indicates that the SOC of the batteries 50 of thesecond drive system 30 is equal to the second prescribed value or thatthe SOC of the batteries 50 of the second drive system 30 is higher thanthe second prescribed value. In the subsequent steps S8 and S9, the SOCequalization control is performed.

At step S8, the electric motor control section 90 decreases the outputpower of the cruise electric motors 24C of the second drive system 30,to be smaller than the output power command value. After this, theprocess moves to step S9. Due to the processing of step S8, the consumedelectric power of the cruise electric motors 24C of the second drivesystem 30 is decreased. Furthermore, if other conditions are constant,the thrust generated due to the cruise electric motors 24C of the seconddrive system 30 driving the cruise rotors 22C decreases.

At step S9, the electric motor control section 90 increases the outputpower of the cruise electric motors 24C of the first drive system 28, tobe greater than the output power command value. After this, the processmoves to step S10. Due to the processing of step S9, the consumedelectric power of the cruise electric motors 24C of the first drivesystem 28 is increased. Furthermore, if other conditions are constant,the thrust generated due to the cruise electric motors 24C of the firstdrive system 28 driving the cruise rotors 22C increases.

At step S9, the thrust generated due to the cruise electric motors 24Cof the first drive system 28 driving the cruise rotors 22C is increasedby an amount corresponding to the amount of the decrease of the thrustgenerated due to the cruise electric motors 24C of the second drivesystem 30 driving the cruise rotors 22C in step S8. As a result, the sumof the thrust generated due to the cruise electric motors 24C of thefirst drive system 28 driving the cruise rotors 22C and the thrustgenerated due to the cruise electric motors 24C of the second drivesystem 30 driving the cruise rotors 22C is kept the same before andafter the SOC equalization control.

At step S10, the electric motor control section 90 determines whetherthe difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30is less than a third prescribed value. If the difference between the SOCof the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 is less than the thirdprescribed value, the output power control ends. If the differencebetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 is greater than orequal to the third prescribed value, the process of step S10 isrepeated.

The third prescribed value is a value for determining that the SOC ofthe batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 have become approximatelyequal. The third prescribed value is set to be smaller than the firstprescribed value.

FIG. 5 is a schematic view of the power supply system 26. FIG. 5schematically shows only the connection relationship among the firstpower generator 46 a, the second power generator 46 b, the batteries 50of the first drive system 28 (first battery 50 a and second battery 50b), the batteries 50 of the second drive system 30 (third battery 50 cand fourth battery 50 d), the cruise electric motors 24C of the firstdrive system 28 (electric motor 24C1_1 and electric motor 24C3_1), andthe cruise electric motors 24C of the second drive system 30 (electricmotor 24C2_2 and electric motor 24C4_2). The generated electric power,charged electric power, and consumed electric power shown in FIG. 5 areexamples in a case where the electric motor control section 90 controlseach cruise electric motor 24C to make the output power thereof equal tothe output power command value.

The example shown in FIG. 5 is an example in which the total consumedelectric power of the cruise electric motors 24C of the first drivesystem 28 is less than the generated electric power generated by thefirst power generator 46 a, and the batteries 50 of the first drivesystem 28 are charged with the excess electric power. Furthermore, theexample shown in FIG. 5 is an example in which the total consumedelectric power of the cruise electric motors 24C of the second drivesystem 30 is less than the generated electric power generated by thesecond power generator 46 b, and the batteries 50 of the second drivesystem 30 are charged with the excess electric power.

In the example shown in FIG. 5 , the charged electric power of thebatteries 50 of the first drive system 28 and the charged electric powerof the batteries 50 of the second drive system 30 are equal. Therefore,in the example shown in FIG. 5 , a state is maintained in which there isa difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30.

FIG. 6 is a schematic view of the power supply system 26. The generatedelectric power, charged electric power, and consumed electric powershown in FIG. 6 are examples in a case where each cruise electric motor24C is controlled according to the SOC equalization control.

The electric motor control section 90 decreases the output power of thecruise electric motors 24C of the first drive system 28, to be less thanthe output power command value. Furthermore, the electric motor controlsection 90 increases the output power of the cruise electric motors 24Cof the second drive system 30, to be greater than the output powercommand value. Due to this, the consumed electric power of the cruiseelectric motors 24C of the first drive system 28 becomes less than theconsumed electric power of the cruise electric motors 24C of the seconddrive system 30. As a result, the charged electric power of thebatteries 50 of the first drive system 28 becomes greater than thecharged electric power of the batteries 50 of the second drive system30. Therefore, the difference between the SOC of the batteries 50 of thefirst drive system 28 and the SOC of the batteries 50 of the seconddrive system 30 becomes smaller.

If other conditions are constant, the thrust generated due to the cruiseelectric motors 24C of the first drive system 28 driving the cruiserotors 22C decreases due to the output power of the cruise electricmotors 24C of the first drive system 28 being decreased. In contrast tothis, the thrust generated due to the cruise electric motors 24C of thesecond drive system 30 driving the cruise rotors 22C increases due tothe output power of the cruise electric motors 24C of the second drivesystem 30 being increased. Therefore, the sum of the thrust generateddue to the cruise electric motors 24C of the first drive system 28driving the cruise rotors 22C and the thrust generated due to the cruiseelectric motors 24C of the second drive system 30 driving the cruiserotors 22C is kept the same before and after the SOC equalizationcontrol.

FIG. 7 is a graph showing the change over time of the SOC of eachbattery 50. The solid line in the graph of FIG. 7 indicates the changeover time of the SOC of the batteries 50 of the first drive system 28.The dotted line in the graph of FIG. 7 indicates the change over time ofthe SOC of the batteries 50 of the second drive system 30.

A disturbance occurs at the timing t1, and the difference between theSOC of the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 becomes greater than or equalto the first prescribed value at the timing t2. The SOC of the batteries50 of the first drive system 28 at the timing t2 is less than the secondprescribed value.

Therefore, at the timing t2, the SOC equalization control is started.The difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30becomes smaller due to the SOC equalization control.

When the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 becomeapproximately equal at the timing t3, the SOC equalization control ends.

Operational Effect

As described above, there are cases where, when the fuselage 12experiences a disturbance such as a crosswind, the output power of someof the VTOL electric motors 20V is increased to be greater than theoutput power of other VTOL electric motors 20V, in order to fix theattitude of the fuselage 12. In this case, a difference can occurbetween the SOCs of the respective batteries 50.

When a difference occurs between the SOCs of respective batteries 50,there is a possibility that there is insufficient electric power forsome load modules 36, despite sufficient electric power being able to besupplied to other load modules 36.

With the flight controller 80 of the present embodiment, the electricmotor control section 90 performs the SOC equalization control in thefollowing case. The following case is a case where the differencebetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 is greater than orequal to the first prescribed value, and the SOC of the batteries 50 ofthe first drive system 28 is less than the second prescribed value.

Furthermore, if the SOC of the batteries 50 of the first drive system 28is lower than the SOC of the batteries 50 of the second drive system 30,the electric motor control section 90 decreases the output power of thecruise electric motors 24C of the first drive system 28 to be less thanthe output power command value. Due to this, the charged electric powerof the batteries 50 of the first drive system 28 can be increased thanbefore the output power of the cruise electric motors 24C of the firstdrive system 28 is decreased. As a result, the SOC of the batteries 50of the first drive system 28 and the SOC of the batteries 50 of thesecond drive system 30 can be made approximately equal.

In the manner described above, when the output power of the cruiseelectric motors 24C of the first drive system 28 is decreased, thethrust generated due to the cruise electric motors 24C of the firstdrive system 28 driving the cruise rotors 22C is decreased.

Therefore, with the flight controller 80 of the present embodiment, theelectric motor control section 90 increases the output power of thecruise electric motors 24C of the second drive system 30 to be greaterthan the output power command value. Due to this, the thrust generateddue to the cruise electric motors 24C of the second drive system 30driving the cruise rotors 22C is increased by an amount corresponding tothe amount of the decrease of the thrust generated due to the cruiseelectric motors 24C of the first drive system 28 driving the cruiserotors 22C. As a result, the sum of the thrust generated due to thecruise electric motors 24C of the first drive system 28 driving thecruise rotors 22C and the thrust generated due to the cruise electricmotors 24C of the second drive system 30 driving the cruise rotors 22Ccan be kept the same before and after the SOC equalization control.

In the aircraft 10 of the present embodiment, among the cruise rotors22C arranged on the left side of the center line A of the fuselage 12,the number of cruise rotors 22C driven by the cruise electric motors 24Cof the first drive system 28 and the number of cruise rotors 22C drivenby the cruise electric motors 24C of the second drive system 30 are thesame.

Due to this, when the output power of the cruise electric motors 24C ofthe first drive system 28 is decreased and the output power of thecruise electric motors 24C of the second drive system 30 is increased,the thrust of the cruise rotor 22C positioned on the left side of thefuselage 12 and the thrust of the cruise rotor 22C positioned on theright side of the fuselage 12 can be made approximately equal. Due tothis, the attitude of the fuselage 12 can be stabilized.

Second Embodiment

With the flight controller 80 of the first embodiment, in the SOCequalization control, the electric motor control section 90 controls theoutput power of each cruise electric motor 24C to adjust the consumedelectric power of each cruise electric motor 24C. In contrast to this,with the flight controller 80 of the present embodiment, in the SOCequalization control, the electric motor control section 90 controls theoutput power of each VTOL electric motor 20V to adjust the consumedelectric power of each VTOL electric motor 20V. The configuration of theaircraft 10, the configuration of the power supply system 26, and theconfiguration of the flight controller 80 in the present embodiment arethe same as those in the first embodiment.

SOC Equalization Control

FIG. 8 is a flow chart showing a process of output power control. Theoutput power control is performed by the electric motor control section90. This output power control is performed repeatedly at prescribedintervals, while the aircraft 10 is operating.

At step S21, the electric motor control section 90 controls each VTOLelectric motor 20V and each cruise electric motor 24C, based on theoutput power command value. After this, the process moves to step S22.

At step S22, the electric motor control section 90 determines whetherthe difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30is greater than or equal to the first prescribed value. If thedifference between the SOC of the batteries 50 of the first drive system28 and the SOC of the batteries 50 of the second drive system 30 isgreater than or equal to the first prescribed value, the process movesto step S23. If the difference between the SOC of the batteries 50 ofthe first drive system 28 and the SOC of the batteries 50 of the seconddrive system 30 is less than the first prescribed value, the outputpower control ends.

At step S23, the electric motor control section 90 determines whetherthe SOC of the batteries 50 of the first drive system 28 is lower thanthe SOC of the batteries 50 of the second drive system 30. If the SOC ofthe batteries 50 of the first drive system 28 is lower than the SOC ofthe batteries 50 of the second drive system 30, the process moves tostep S24. If the SOC of the batteries 50 of the first drive system 28 ishigher than the SOC of the batteries 50 of the second drive system 30,the process moves to step S27.

At step S24, the electric motor control section 90 determines whetherthe SOC of the batteries 50 of the first drive system 28 is less thanthe second prescribed value. If the SOC of the batteries 50 of the firstdrive system 28 is less than the second prescribed value, the processmoves to step S25. If the SOC of the batteries 50 of the first drivesystem 28 is greater than or equal to the second prescribed value, theoutput power control ends. The SOC of the batteries 50 of the firstdrive system 28 being less than the second prescribed value indicatesthat the SOC of the batteries 50 of the first drive system 28 is lowerthan the second prescribed value. The SOC of the batteries 50 of thefirst drive system 28 being greater than or equal to the secondprescribed value indicates that the SOC of the batteries 50 of the firstdrive system 28 is equal to the second prescribed value or that the SOCof the batteries 50 of the first drive system 28 is higher than thesecond prescribed value. In the subsequent steps S25 and S26, the SOCequalization control is performed.

At step S25, the electric motor control section 90 decreases the outputpower of the VTOL electric motors 20V of the first drive system 28, tobe smaller than the output power command value. After this, the processmoves to step S26. Due to the processing of step S25, the consumedelectric power of the VTOL electric motors 20V of the first drive system28 is decreased. Furthermore, if other conditions are constant, thethrust generated due to the VTOL electric motors 20V of the first drivesystem 28 driving the VTOL rotors 18V decreases.

At step S26, the electric motor control section 90 increases the outputpower of the VTOL electric motors 20V of the second drive system 30, tobe greater than the output power command value. After this, the processmoves to step S30. Due to the processing of step S26, the consumedelectric power of the VTOL electric motors 20V of the second drivesystem 30 is increased. Furthermore, if other conditions are constant,the thrust generated due to the VTOL electric motors 20V of the seconddrive system 30 driving the VTOL rotors 18V increases.

At step S26, the thrust generated due to the VTOL electric motors 20V ofthe second drive system 30 driving the VTOL rotors 18V is increased byan amount corresponding to the amount of the decrease of the thrustgenerated due to the VTOL electric motors 20V of the first drive system28 driving the VTOL rotors 18V in step S25. As a result, the sum of thethrust generated due to the VTOL electric motors 20V of the first drivesystem 28 driving the VTOL rotors 18V and the thrust generated due tothe VTOL electric motors 20V of the second drive system 30 driving theVTOL rotors 18V is kept the same before and after the SOC equalizationcontrol.

At step S27, the electric motor control section 90 determines whetherthe SOC of the batteries 50 of the second drive system 30 is less thanthe second prescribed value. If the SOC of the batteries 50 of thesecond drive system 30 is less than the second prescribed value, theprocess moves to step S28. If the SOC of the batteries 50 of the seconddrive system 30 is greater than or equal to the second prescribed value,the output power control ends. The SOC of the batteries 50 of the seconddrive system 30 being less than the second prescribed value indicatesthat the SOC of the batteries 50 of the second drive system 30 is lowerthan the second prescribed value. The SOC of the batteries 50 of thesecond drive system 30 being greater than or equal to the secondprescribed value indicates that the SOC of the batteries 50 of thesecond drive system 30 is equal to the second prescribed value or thatthe SOC of the batteries 50 of the second drive system 30 is higher thanthe second prescribed value. In the subsequent steps S28 and S29, theSOC equalization control is performed.

At step S28, the electric motor control section 90 decreases the outputpower of the VTOL electric motors 20V of the second drive system 30, tobe smaller than the output power command value. After this, the processmoves to step S29. Due to the processing of step S28, the consumedelectric power of the VTOL electric motors 20V of the second drivesystem 30 is decreased. Furthermore, if other conditions are constant,the thrust generated due to the VTOL electric motors 20V of the seconddrive system 30 driving the VTOL rotors 18V decreases.

At step S29, the electric motor control section 90 increases the outputpower of the VTOL electric motors 20V of the first drive system 28, tobe greater than the output power command value. After this, the processmoves to step S30. Due to the processing of step S29, the consumedelectric power of the VTOL electric motors 20V of the first drive system28 is increased. Furthermore, if other conditions are constant, thethrust generated due to the VTOL electric motors 20V of the first drivesystem 28 driving the VTOL rotors 18V increases.

At step S29, the thrust generated due to the VTOL electric motors 20V ofthe first drive system 28 driving the VTOL rotors 18V is increased by anamount corresponding to the amount of the decrease of the thrustgenerated due to the VTOL electric motors 20V of the second drive system30 driving the VTOL rotors 18V in step S28. As a result, the sum of thethrust generated due to the VTOL electric motors 20V of the first drivesystem 28 driving the VTOL rotors 18V and the thrust generated due tothe VTOL electric motors 20V of the second drive system 30 driving theVTOL rotors 18V is kept the same before and after the SOC equalizationcontrol.

At step S30, the electric motor control section 90 determines whetherthe difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30is less than the third prescribed value. If the difference between theSOC of the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 is less than the thirdprescribed value, the output power control ends. If the differencebetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 is greater than orequal to the third prescribed value, the process of step S30 isrepeated.

Case of Battery Discharging

FIG. 9 is a schematic view of the power supply system 26. FIG. 9schematically shows only the connection relationship among the firstpower generator 46 a, the second power generator 46 b, the batteries 50of the first drive system 28 (first battery 50 a and second battery 50b), the batteries 50 of the second drive system 30 (third battery 50 cand fourth battery 50 d), the VTOL electric motors 20V of the firstdrive system 28 (electric motor 20V1_1, electric motor 20V4_1, electricmotor 20V5_1, and electric motor 20V8_1), and the VTOL electric motors20V of the second drive system 30 (electric motor 20V2_2, electric motor20V3_2, electric motor 20V6_2, and electric motor 20V7_2). The generatedelectric power, discharged electric power, and consumed electric powershown in FIG. 9 are examples in a case where the electric motor controlsection 90 controls each VTOL electric motor 20V to make the outputpower thereof equal to the output power command value.

The example shown in FIG. 9 is an example in which the total consumedelectric power of the VTOL electric motors 20V of the first drive system28 is greater than the generated electric power generated by the firstpower generator 46 a, and the batteries 50 of the first drive system 28are discharged. Furthermore, the example shown in FIG. 9 is an examplein which the total consumed electric power of the VTOL electric motors20V of the second drive system 30 is greater than the generated electricpower generated by the second power generator 46 b, and the batteries 50of the second drive system 30 are discharged.

In the example shown in FIG. 9 , the discharged electric power of thebatteries 50 of the first drive system 28 and the discharged electricpower of the batteries 50 of the second drive system 30 are equal.Therefore, in the example shown in FIG. 9 , a state is maintained inwhich there is a difference between the SOC of the batteries 50 of thefirst drive system 28 and the SOC of the batteries 50 of the seconddrive system 30.

FIG. 10 is a schematic view of the power supply system 26. The generatedelectric power, discharged electric power, and consumed electric powershown in FIG. 10 are examples in a case where each VTOL electric motor20V is controlled according to the SOC equalization control.

The electric motor control section 90 decreases the output power of theVTOL electric motors 20V of the first drive system 28, to be less thanthe output power command value. Furthermore, the electric motor controlsection 90 increases the output power of the VTOL electric motors 20V ofthe second drive system 30, to be greater than the output power commandvalue. Due to this, the consumed electric power of the VTOL electricmotors 20V of the first drive system 28 becomes less than the consumedelectric power of the VTOL electric motors 20V of the second drivesystem 30. As a result, the discharged electric power of the batteries50 of the first drive system 28 becomes less than the dischargedelectric power of the batteries 50 of the second drive system 30.Therefore, the difference between the SOC of the batteries 50 of thefirst drive system 28 and the SOC of the batteries 50 of the seconddrive system 30 becomes smaller.

If other conditions are constant, the thrust generated due to the VTOLelectric motors 20V of the first drive system 28 driving the VTOL rotors18V decreases due to the output power of the VTOL electric motors 20V ofthe first drive system 28 being decreased. In contrast to this, thethrust generated due to the VTOL electric motors 20V of the second drivesystem 30 driving the VTOL rotors 18V increases due to the output powerof the VTOL electric motors 20V of the second drive system 30 beingincreased. As a result, the sum of the thrust generated due to the VTOLelectric motors 20V of the first drive system 28 driving the VTOL rotors18V and the thrust generated due to the VTOL electric motors 20V of thesecond drive system 30 driving the VTOL rotors 18V is kept the samebefore and after the SOC equalization control.

FIG. 11 is a graph showing the change over time of the SOC of eachbattery 50. The solid line in the graph of FIG. 11 indicates the changeover time of the SOC of the batteries 50 of the first drive system 28.The dotted line in the graph of FIG. 11 indicates the change over timeof the SOC of the batteries 50 of the second drive system 30.

A disturbance occurs at the timing t11, and the difference between theSOC of the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 becomes greater than or equalto the first prescribed value at the timing t12. The SOC of thebatteries 50 of the first drive system 28 at the timing t12 is less thanthe second prescribed value.

Therefore, at the timing t12, the SOC equalization control is started.The difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30becomes smaller due to the SOC equalization control.

When the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 becomeapproximately equal at the timing t13, the SOC equalization controlends.

Case of Battery Charging

FIG. 12 is a schematic view of the power supply system 26. FIG. 12schematically shows only the connection relationship among the firstpower generator 46 a, the second power generator 46 b, the batteries 50of the first drive system 28 (first battery 50 a and second battery 50b), the batteries 50 of the second drive system 30 (third battery 50 cand fourth battery 50 d), the VTOL electric motors 20V of the firstdrive system 28 (electric motor 20V1_1, electric motor 20V4_1, electricmotor 20V5_1, and electric motor 20V8_1), and the VTOL electric motors20V of the second drive system 30 (electric motor 20V2_2, electric motor20V3_2, electric motor 20V6_2, and electric motor 20V7_2). The generatedelectric power, charged electric power, and consumed electric powershown in FIG. 12 are examples in a case where each VTOL electric motor20V is controlled based on the output power command value.

The example shown in FIG. 12 is an example in which the total consumedelectric power of the VTOL electric motors 20V of the first drive system28 is less than the generated electric power generated by the firstpower generator 46 a, and the batteries 50 of the first drive system 28are charged with the excess electric power. Furthermore, the exampleshown in FIG. 12 is an example in which the total consumed electricpower of the VTOL electric motors 20V of the second drive system 30 isless than the generated electric power generated by the second powergenerator 46 b, and the batteries 50 of the second drive system 30 arecharged with the excess electric power.

In the example shown in FIG. 12 , the charged electric power of thebatteries 50 of the first drive system 28 and the charged electric powerof the batteries 50 of the second drive system 30 are equal. Therefore,in the example shown in FIG. 12 , a state is maintained in which thereis a difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30.

FIG. 13 is a schematic view of the power supply system 26. The generatedelectric power, charged electric power, and consumed electric powershown in FIG. 13 are examples in a case where each VTOL electric motor20V is controlled according to the SOC equalization control.

The electric motor control section 90 decreases the output power of theVTOL electric motors 20V of the first drive system 28, to be less thanthe output power command value. Furthermore, the electric motor controlsection 90 increases the output power of the VTOL electric motors 20V ofthe second drive system 30, to be greater than the output power commandvalue. Due to this, the consumed electric power of the VTOL electricmotors 20V of the first drive system 28 becomes less than the consumedelectric power of the VTOL electric motors 20V of the second drivesystem 30. As a result, the charged electric power of the batteries 50of the first drive system 28 becomes greater than the charged electricpower of the batteries 50 of the second drive system 30. Therefore, thedifference between the SOC of the batteries 50 of the first drive system28 and the SOC of the batteries 50 of the second drive system 30 becomessmaller.

If other conditions are constant, the thrust generated due to the VTOLelectric motors 20V of the first drive system 28 driving the VTOL rotors18V decreases due to the output power of the VTOL electric motors 20V ofthe first drive system 28 being decreased. In contrast to this, thethrust generated due to the VTOL electric motors 20V of the second drivesystem 30 driving the VTOL rotors 18V increases due to the output powerof the VTOL electric motors 20V of the second drive system 30 beingincreased. As a result, the sum of the thrust generated due to the VTOLelectric motors 20V of the first drive system 28 driving the VTOL rotors18V and the thrust generated due to the VTOL electric motors 20V of thesecond drive system 30 driving the VTOL rotors 18V is kept the samebefore and after the SOC equalization control.

FIG. 14 is a graph showing the change over time of the SOC of eachbattery 50. The solid line in the graph of FIG. 14 indicates the changeover time of the SOC of the batteries 50 of the first drive system 28.The dotted line in the graph of FIG. 14 indicates the change over timeof the SOC of the batteries 50 of the second drive system 30.

A disturbance occurs at the timing t21, and the difference between theSOC of the batteries 50 of the first drive system 28 and the SOC of thebatteries 50 of the second drive system 30 becomes greater than or equalto the first prescribed value at the timing t22. The SOC of thebatteries 50 of the first drive system 28 at the timing t22 is less thanthe second prescribed value.

Therefore, at the timing t22, the SOC equalization control is started.The difference between the SOC of the batteries 50 of the first drivesystem 28 and the SOC of the batteries 50 of the second drive system 30becomes smaller due to the SOC equalization control.

When the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 becomeapproximately equal at the timing t23, the SOC equalization controlends.

Operational Effect

With the flight controller 80 of the present embodiment, the electricmotor control section 90 performs the SOC equalization control in thefollowing case. The following case is a case where the differencebetween the SOC of the batteries 50 of the first drive system 28 and theSOC of the batteries 50 of the second drive system 30 is greater than orequal to the first prescribed value, and the SOC of the batteries 50 ofthe first drive system 28 is less than the second prescribed value.

Furthermore, if the SOC of the batteries 50 of the first drive system 28is lower than the SOC of the batteries 50 of the second drive system 30,the electric motor control section 90 decreases the output power of theVTOL electric motors 20V of the first drive system 28 to be less thanthe output power command value. Due to this, the charged electric powerof the batteries 50 of the first drive system 28 can be increased thanbefore the output power of the VTOL electric motors 20V of the firstdrive system 28 is decreased. As a result, the SOC of the batteries 50of the first drive system 28 and the SOC of the batteries 50 of thesecond drive system 30 can be made approximately equal.

In the manner described above, when the output power of the VTOLelectric motors 20V of the first drive system 28 is decreased to be lessthan the output power command value, the thrust generated by the VTOLrotors 18V of the first drive system 28 is decreased.

Therefore, with the flight controller 80 of the present embodiment, theelectric motor control section 90 increases the output power of the VTOLelectric motors 20V of the second drive system 30, to be greater thanthe output power command value. Due to this, the thrust generated due tothe VTOL electric motors 20V of the second drive system 30 driving theVTOL rotors 18V is increased by an amount corresponding to the amount ofthe decrease of the thrust generated due to the VTOL electric motors 20Vof the first drive system 28 driving the VTOL rotors 18V. As a result,the sum of the thrust generated due to the VTOL electric motors 20V ofthe first drive system 28 driving the VTOL rotors 18V and the thrustgenerated due to the VTOL electric motors 20V of the second drive system30 driving the VTOL rotors 18V can be kept the same before and after theSOC equalization control.

With the aircraft 10 of the present embodiment, among the VTOL rotors18V arranged on the left side of the center line A of the fuselage 12,the number of VTOL rotors 18V driven by the VTOL electric motors 20V ofthe first drive system 28 and the number of VTOL rotors 18V driven bythe VTOL electric motors 20V of the second drive system 30 are the same.

Due to this, when the output power of the VTOL electric motors 20V ofthe first drive system 28 is decreased and the output power of the VTOLelectric motors 20V of the second drive system 30 is increased, thetotal thrust of the VTOL rotors 18V positioned on the left side of thefuselage 12 and the total thrust of the VTOL rotors 18V positioned onthe right side of the fuselage 12 can be made approximately equal. Dueto this, the attitude of the fuselage 12 can be stabilized.

The present invention is not limited to the above disclosure, andvarious modifications are possible without departing from the essenceand gist of the present invention.

In the flight controller 80 of the first embodiment, the sum of thethrust generated due to the cruise electric motors 24C of the firstdrive system 28 driving the cruise rotors 22C and the thrust generateddue to the cruise electric motors 24C of the second drive system 30driving the cruise rotors 22C is kept the same before and after the SOCequalization control. In contrast to this, the sum of the thrustgenerated due to the cruise electric motors 24C of the first drivesystem 28 driving the cruise rotors 22C and the thrust generated due tothe cruise electric motors 24C of the second drive system 30 driving thecruise rotors 22C may be lower after the SOC equalization control thanbefore the SOC equalization control.

In the first embodiment and the second embodiment, the first powersupply circuit 38 a and the second power supply circuit 38 b areprovided independently, and are not connected to each other. In contrastto this, the first power supply circuit 38 a and the second power supplycircuit 38 b may be connected to each other. In such a case, eachbattery 50 is connected in parallel to both the first main power sourceapparatus 32 a and the second main power source apparatus 32 b.Therefore, even when the equalization control is not performed, the SOCsof the respective batteries 50 can be made approximately equal. However,the SOCs of the respective batteries can be made approximately equal ina short time by performing the equalization control.

In the first embodiment and the second embodiment, one cruise rotor 22Cis provided on the left side and one cruise rotor 22C is provided on theright side of the center line A of the fuselage 12. In contrast to this,two cruise rotors 22C may be provided on the left side and two cruiserotors 22C may be provided on the right side of the fuselage 12. In sucha case, one cruise rotor 22C is driven by one cruise electric motor 24C.Furthermore, one cruise rotor 22C may be provided in the center of thefuselage 12 in the left-right direction. In such a case, the one cruiserotor 22C is driven by two cruise electric motors 24C.

The VTOL rotors 18V and the cruise rotors 22C of the first embodimentand second embodiment may be coaxial rotors. One of the two coaxialrotors may be driven by the electric motor of the first drive system 28and the other rotor may be driven by the electric motor of the seconddrive system 30.

Invention Obtainable from the Embodiments

The invention that can be understood from the above embodiments will bedescribed below.

Provided is the control apparatus (80) for the aircraft (10), theaircraft including: at least one power generator (46) configured togenerate electric power; at least one first battery (50 a, 50 b)configured to store electric power; at least one first electric motor(20V1_1, 20V4_1, 20V5_1, 20V8_1, 24C1_1, 24C3_1) configured to operateusing electric power supplied from the power generator and the firstbattery; at least one first diode (76) having the anode connected to thepower generator side, and the cathode connected to the first batteryside; at least one second battery (50 c, 50 d) configured to storeelectric power; at least one second electric motor (20V2_2, 20V3_2,20V6_2, 20V7_2, 24C2_2, 24C4_2) configured to operate using electricpower supplied from the power generator and the second battery; at leastone second diode (76) having the anode connected to the power generatorside, and the cathode connected to the second battery side; and theplurality of rotors (18V, 22C) configured to generate thrust acting onthe fuselage (12). The control apparatus comprises: the electric motorcontrol section (90) configured to control each of the first electricmotor and the second electric motor; and the battery monitoring section(88) configured to monitor the SOC (State Of Charge) of each of thefirst battery and the second battery. Each of the rotors is driven byone of the first electric motor or the second electric motor, or by boththe first electric motor and the second electric motor. In a case wherethe difference between the SOC of the first battery and the SOC of thesecond battery is greater than or equal to the first prescribed value,and the SOC of the first battery is lower than the SOC of the secondbattery, the electric motor control section decreases thrust generateddue to the first electric motor driving the rotor to reduce consumedelectric power of the first electric motor and also increases thrustgenerated due to the second electric motor driving the rotor, comparedto a case where the difference between the SOC of the first battery andthe SOC of the second battery is less than the first prescribed value.Due to this, the SOCs of the respective batteries can be madeapproximately equal.

In the control apparatus for the aircraft described above, in a casewhere the difference between the SOC of the first battery and the SOC ofthe second battery is greater than or equal to the first prescribedvalue, the SOC of the first battery is lower than the SOC of the secondbattery, and the SOC of the first battery is less than the secondprescribed value, the electric motor control section may decrease thethrust generated due to the first electric motor driving the rotor toreduce the consumed electric power of the first electric motor and alsoincrease the thrust generated due to the second electric motor drivingthe rotor, compared to the case where the difference between the SOC ofthe first battery and the SOC of the second battery is less than thefirst prescribed value. Due to this, the SOCs of the respectivebatteries can be made

In the control apparatus for the aircraft described above, the firstelectric motor and the second electric motor may each drive thehorizontal rotor (22C) configured to generate thrust in the horizontaldirection; and in the case where the difference between the SOC of thefirst battery and the SOC of the second battery is greater than or equalto the first prescribed value, and the SOC of the first battery is lowerthan the SOC of the second battery, the electric motor control sectionmay decrease the sum of thrust generated due to the first electric motordriving the horizontal rotor and thrust generated due to the secondelectric motor driving the horizontal rotor, compared to the case wherethe difference between the SOC of the first battery and the SOC of thesecond battery is less than the first prescribed value. Due to this, theSOCs of the respective batteries can be made approximately equal at anearly stage.

In the control apparatus for the aircraft described above, the firstelectric motor and the second electric motor may each drive thehorizontal rotor configured to generate thrust in the horizontaldirection; and in the case where the difference between the SOC of thefirst battery and the SOC of the second battery is greater than or equalto the first prescribed value, the SOC of the first battery is lowerthan the SOC of the second battery, and the SOC of the first battery isless than the second prescribed value, the electric motor controlsection may decrease the sum of thrust generated due to the firstelectric motor driving the horizontal rotor and thrust generated due tothe second electric motor driving the horizontal rotor, compared to thecase where the difference between the SOC of the first battery and theSOC of the second battery is less than the first prescribed value. Dueto this, the SOCs of the respective batteries can be made approximatelyequal at an early stage.

In the control apparatus for the aircraft described above, the number ofthe rotors arranged on one side of the center line of the fuselage inthe left-right direction may be the same as the number of the rotorsarranged on the other side of the center line; among the rotors arrangedon the one side, the number of the rotors driven by the first electricmotor may be the same as the number of the rotors driven by the secondelectric motor; and among the rotors arranged on the other side, thenumber of the rotors driven by the first electric motor may be the sameas the number of the rotors driven by the second electric motor. Due tothis, the magnitude of the thrust generated by the rotors can be madeapproximately equal on the left and right of the fuselage. As a result,the attitude of the fuselage can be stabilized.

In the control apparatus for the aircraft described above, each of therotors may be the vertical rotor (18V) configured to generate thrust inthe vertical direction or the horizontal rotor configured to generatethrust in the horizontal direction. Due to this, the SOCs of therespective batteries serving as power sources of the electric motorsdriving the vertical rotors and horizontal rotors can be madeapproximately equal.

In the control apparatus for the aircraft described above, at least oneof the plurality of rotors may be the horizontal rotor configured togenerate thrust in the horizontal direction; and the horizontal rotormay be driven by both the first electric motor and the second electricmotor. Due to this, the SOCs of the respective batteries serving aspower sources of the electric motors driving the horizontal rotors canbe made

1. A control apparatus for an aircraft, the aircraft including: at leastone power generator configured to generate electric power; at least onefirst battery configured to store electric power; at least one firstelectric motor configured to operate using electric power supplied fromthe power generator and the first battery; at least one first diodeincluding an anode connected to a side of the power generator, and acathode connected to a side of the first battery; at least one secondbattery configured to store electric power; at least one second electricmotor configured to operate using electric power supplied from the powergenerator and the second battery; at least one second diode including ananode connected to the side of the power generator, and a cathodeconnected to a side of the second battery; and a plurality of rotorsconfigured to generate thrust acting on a fuselage, wherein each of therotors is driven by one of the first electric motor or the secondelectric motor, or by both the first electric motor and the secondelectric motor, the control apparatus comprising one or more processorsthat execute computer-executable instructions stored in a memory,wherein the one or more processors execute the computer-executableinstructions to cause the control device to: control each of the firstelectric motor and the second electric motor; monitor a state of chargeof each of the first battery and the second battery, and in a case wherea difference between the state of charge of the first battery and thestate of charge of the second battery is greater than or equal to afirst prescribed value, and the state of charge of the first battery islower than the state of charge of the second battery, decrease thrustgenerated due to the first electric motor driving the rotor to reduceconsumed electric power of the first electric motor, and also increasethrust generated due to the second electric motor driving the rotor,compared to a case where the difference between the state of charge ofthe first battery and the state of charge of the second battery is lessthan the first prescribed value.
 2. The control apparatus for theaircraft according to claim 1, wherein in a case where the differencebetween the state of charge of the first battery and the state of chargeof the second battery is greater than or equal to the first prescribedvalue, the state of charge of the first battery is lower than the stateof charge of the second battery, and the state of charge of the firstbattery is less than a second prescribed value, the one or moreprocessors cause the control device to decrease the thrust generated dueto the first electric motor driving the rotor to reduce the consumedelectric power of the first electric motor, and also increase the thrustgenerated due to the second electric motor driving the rotor, comparedto the case where the difference between the state of charge of thefirst battery and the state of charge of the second battery is less thanthe first prescribed value.
 3. The control apparatus for the aircraftaccording to claim 1, wherein the first electric motor and the secondelectric motor each drive a horizontal rotor configured to generatethrust in a horizontal direction, and in the case where the differencebetween the state of charge of the first battery and the state of chargeof the second battery is greater than or equal to the first prescribedvalue, and the state of charge of the first battery is lower than thestate of charge of the second battery, the one or more processors causethe control device to decrease a sum of thrust generated due to thefirst electric motor driving the horizontal rotor and thrust generateddue to the second electric motor driving the horizontal rotor, comparedto the case where the difference between the state of charge of thefirst battery and the state of charge of the second battery is less thanthe first prescribed value.
 4. The control apparatus for the aircraftaccording to claim 2, wherein the first electric motor and the secondelectric motor each drive a horizontal rotor configured to generatethrust in a horizontal direction, and in the case where the differencebetween the state of charge of the first battery and the state of chargeof the second battery is greater than or equal to the first prescribedvalue, the state of charge of the first battery is lower than the stateof charge of the second battery, and the state of charge of the firstbattery is less than the second prescribed value, the one or moreprocessors cause the control device to decrease a sum of thrustgenerated due to the first electric motor driving the horizontal rotorand thrust generated due to the second electric motor driving thehorizontal rotor, compared to the case where the difference between thestate of charge of the first battery and the state of charge of thesecond battery is less than the first prescribed value.
 5. The controlapparatus for the aircraft according to claim 1, wherein a number of therotors arranged on one side of a center line of the fuselage in aleft-right direction is equal to a number of the rotors arranged onanother side of the center line, among the rotors arranged on the oneside, a number of the rotors driven by the first electric motor is equalto a number of the rotors driven by the second electric motor, and amongthe rotors arranged on the other side, a number of the rotors driven bythe first electric motor is equal to a number of the rotors driven bythe second electric motor.
 6. The control apparatus for the aircraftaccording to claim 1, wherein each of the rotors is a vertical rotorconfigured to generate thrust in a vertical direction or a horizontalrotor configured to generate thrust in a horizontal direction.
 7. Thecontrol apparatus for the aircraft according to claim 1, wherein atleast one of the plurality of rotors is a horizontal rotor configured togenerate thrust in a horizontal direction, and the horizontal rotor isdriven by both the first electric motor and the second electric motor.